(Ben Balter)For college students, it’s a wonderful thing to find a store willing to pay more than a pittance to buy back the textbooks you’ve been pretending to read all semester. People who discovered the Boston-based site Valore Books were happy with the estimates they got for the value of their books, but less happy when their checks failed to show up. There are plenty of complaints online about every business, but Valore has an awful lot, including complaints to the Better Business Bureau.